Conduct disorders in preteens are predictive of eventual teenage serious violent and delinquent behavior, according to a new study from the Université de Montréal. The findings, published in this month's issue of Journal of Child Psychology and Psychiatry, have implications for concerned parents.

Preteens who steal, destroy property, fight and bully are six times as likely to sell illicit drugs, nine times as likely to join a gang, 11 times as likely to carry a weapon and eight times as likely to be arrested as a future teenager, according to principle author, Éric Lacourse, a researcher at the Groupe de recherche sur l'inadaptation psychosociale chez l'enfant (GRIP) at the Université de Montréal.

“At ages 12 and 13, the behaviors that lead to delinquency are well documented,” says Lacourse. “However, intervention programs are mostly targeted to younger children and very little help is available for kids preteens.”

Two-year studyThe study examined three groups of 12 and 13-year-old Canadian kids over a span of two years. The group consisted of 4,125 test-subjects who were classified according to precise symptoms of conduct disorders.

“Children with conduct disorders who are not violent are also more likely to adopt serious delinquent behaviors as teenagers,” says Lacourse. “More specifically, this group is three times as likely to sell illicit drugs, four times as likely to join a gang, and three times as likely to mug someone using a weapon.”

Lacourse believes the definition of conduct disorders in the Diagnostic and Statistical Manual of Mental Disorders (DSM) should be reviewed. Currently, it defines the disorder as a combination of any three symptoms on a list of 15. “The list is partly deficient because it doesn't apply to all cases,” says Lacourse. “And it's also partly wieldy because it allows for 30,000 possible combinations.”

About the study: “Two-year predictive validity of conduct disorder subtypes in early adolescence: a latent class analysis of a Canadian longitudinal sample” was authored by E. Lacourse R. Baillargeon, V. Dupéré, F. Vitaro, E. Romano and R Tremblay from the Université de Montréal.